In Las Vegas we have 3 different sets of rules- but have to change 4 times a year. Winter / Spring & Fall / Summer
The Las Vegas Water District site - https://www.lvvwd.com/conservation/drought_watering_schedule.html
This was actually the main reason I installed two controllers(needed 21 zones) there - I'm often away from this home, and having the ability to update remote is key to avoiding fines for watering at the wrong time.
I've only recently installed the controllers so my plan was to add a total of 3 schedules and just disable the two that aren't active. I don't see this as overly cumbersome, but in the age of automation having start and stop dates on a schedule could make the change over for me